The invention relates to a method for operating an adsorption dryer, in particular a drying cabinet, and such a dryer comprising a receptacle for textile goods which are stored or hung in a stationary manner, a guide for the dry air flow, a heater, an adsorption apparatus having a reversibly dehydratable adsorbent, and at least one blower for generating an air flow, wherein said air flow is routed over the heater, the textile goods to be treated and through the adsorption apparatus.
A device in which the moisture is removed from moisture-enriched air by means of an adsorbent drying agent (adsorbent) is disclosed in the unexamined German application DE 36 26 887 A1. The device claimed in said application, being designed as a clothes dryer, comprises a receptacle container for the goods to be dried, a blower which advances the process air in the closed circuit, a heater unit for heating the process air, and a container for holding a storage medium that works by adsorbing and desorbing water. In the cited unexamined German application, a material based on zeolite is proposed as such a reversibly adsorbing storage medium.
The dryer is operated in such a way that the process air is heated at the beginning of the drying process in order to achieve a suitable operating temperature. As the adsorbent dehumidification by the adsorber becomes effective and the adsorption heat is released accordingly, the supplied heating power is considerably reduced.
The adsorber is arranged in a container in such a way that the air flow for dehumidification and the air flow for desorption of the adsorber can be guided over said adsorber alternately. An additional air guiding system and suitable air guiding control means, in particular control gates, and an additional heater for heating the desorbing air flow are provided for the air flow that is used for desorption of the adsorber.
Also known is an adsorption dryer in which the dry air flow in the closed circuit is guided in opposite directions alternately during the drying process. By virtue of the two-way through-flow, the goods to be dried are more uniformly exposed to the flow or through-flow of the process air, and the time that is required to achieve a desired drying result can be shortened.
The adsorption dryers can be operated very effectively in that the heat energy which is expended during the dehumidification of the goods to be dried can be released and fed back into the process air during adsorption of the moisture by the adsorbent. During the drying process, the adsorbent is used both for dehumidification of the goods to be dried and for heat recovery.
The unexamined Japanese application JP 09-135995 A discloses an adsorption dryer comprising a receptacle for textile goods, a first blower in a first flow channel and a second blower in a second flow channel, an adsorption apparatus comprising a reversibly dehydratable adsorbent and a heater for the desorption thereof. The adsorption dryer performs a textile care process in the “dry” operating mode, at the start of which an automatic decreasing program for removing creases is provided. In this case, ambient air is routed along the first flow channel over the adsorbent, until said adsorbent is sufficiently charged with moisture. As a result of switching on the heater, the adsorbent is then desorbed and the reemerging (desorbed) moisture is routed as steam into the receptacle and over the textile goods in order to remove creases. For the purpose of subsequently drying the de-creased textile goods, ambient air is routed over the adsorbent and into the receptacle. The moisture that then collects in the adsorbent can be removed periodically by switching on the heater and redirecting the process air flow, wherein ambient air that is heated by the heater is guided over the adsorbent and through a cooled heat exchanger, such that the steam emerging from the adsorbent can condense out at the heat exchanger.
The known adsorption dryers have the disadvantage that, following a drying process, the adsorbent has to be desorbed in order to ensure the subsequent operational readiness. The water vapor that is generated in this way must be removed, as condensation from a collection container or directly into the space surrounding the device. The energy that has to be expended during the desorption is comparatively high, whereby the operating costs of such a dryer disadvantageously increase.